Submarine mine.



T. K. NORTH.

SUBMARINE MINE.

APPLICATION FILED JUNE 21.1917.

1 ,299,0 1 2. Patented Apr. 1, 1919.

3 SHEETS-SHEET I.

INVE/V 7'01? 730/7145 /(/1/0r7% ATTORNEYS T. K. NORT H.

SUBMARINE MINE.

APPLICATION FILED JUNE 21. I927.

Patnted Apr. 1, 1919.

3 SHEETS-SHEET 2- M, mm, W :4 6

T. K. NORTH.

SUBMARINE MlNE.

APPLICATION FILED JUNE 21.1911.

1,299,012, Patented Apr. 1,1919.

3 SHEETS-SHEET 3- MM 14 4,49: how/i, JAM-1;

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. TE STATES ATENT OFFICE.

THOMAS KEPPEL NORTH, OF WESTMINSTER, LONDON, ENGLAND, ASSIGNOR TO VICKERS LIMITED, OF WESTMINSTER, ENGLAND.

SUBMARINE MINE.

Specification of Letters Patent.

Patented Apr. '1, 1919.

To all whom it may concern:

. Be it known that l, i'THoMAs KEPPEL NORTH, a subject of the King of Great Britain, residing at Vickers House, Broadway, Westminster, in the county of London, England, have invented certain new and useful Improvements in or Relating to Submarine Mines, of which the following is a specification.

This invention relates to submarine mines of the kind comprising a flotation. chamber, constituting the mine proper, an anchor containing a drum on which is wound a cable connecting the anchor to the flotation chamber and a plummet or sounding ball controlling a ratchet pawl adapted to engage with ratchet teeth on the cable drum of the anchor; this plummet holds the ratchet pawl out of engagement with the ratchet teeth during the descent of the anchor in the water thereby enabling the cable drum to unwind, but when the plummet touches the sea bed the said pawl-is caused to engage with the ratchet teeth and the anchor then draws the flotation chamber beneath the surface of the water till it assumes a depth predetermined by the effective length of the plummet. line.

According to the present invention the pawl is retained in its disengaged position by a spring controlled trigger or sear which is held in engagement with the pawl by the weight of the plummet; when the plummet reaches the sea bed the trigger is moved by its spring into its disengaged position and a spring operating upon the pawl moves the latter into engagement with the ratchet teeth on the anchor cable drum. The said trigger is so constructed that if the weight of the plummet is again exerted upon it, a portion thereof will engage with the pawl and retain it all the more firmly in engagement with the ratchet teeth. It will thus be seen that there is no possibility of the pawl becoming disengaged from the ratchet teeth as a resu t of a pull being exerted upon the plummet line after the plummet has reached the sea bed.

- In order that the said invention may be clearly understood and readily carried into effect, the same will be described more fully with reference to the accompanying drawings, in which Figures 1, 2 and 3 are respectively a sectional side elevation, a sectional end e e tionand a plan of a constructional form of the improvements,

Figs. 4, 5 and 6 are diagrams showing the r essential parts of the improvements in three diffierent positions hereinafter referred to, an

Fig. 7 is a sectional elevation showing the anti-vibration device hereinafter referred to, the parts of this device being shown in the position to allow the pawl to move into engagement with the ratchet teeth on the anchor cable drum, and Figs. 8 and 9 are respectively a sectional side elevation and a sectional end elevation showing the improvements in position on a mine.

A is the ratchet pawl and A, A are the ratchet teeth of the anchor cable drum A (Fig. 9) with which the said pawl is adapted to engage. B is the aforesaid spring controlled trigger or sear connected to the line B of the plummet B (Fig. 9) by a link B.

In the example shown the pawl A, its spring a, all carried upon a plate or bracket C to which the pawl and the trigger are pivoted at a", 79* respectively. The pawl A is provided with a lateral pin A in the path of which normally lies a plunger D forming part of a so-called anti-vibration device for preventing movement of the pawl into engagement with the ratchet teeth until the anchor cable drum has made a predetermined number of revolutions. This pin is formed with a flat face a for engagement with the nose B of the trigger B.

The said antivibration device is well known and comprises a nut D mounted on the screw-threaded end of the shaft A to which the drum A is connected, the said nut, prior to the launching of the mine, 00- cupying the position shown by Fig. 9 in which it blocks the movement of the plunger D away from the pin A The nut D is prevented from rotating but is free to move axially so that as the drum rotates the nut is gradually moved into the position shown by Fig. 7 in which the plunger D is free to be moved by its spring away from the pin A The spring a can then shift the pawl B into the position shown by Fig. 4 with the face a in contact with the nose B of the trigger. When the plummet reaches the sea bed and no longer exerts a pull on the g r B, the p ing 71 i places the said the trigger B and its spring b are 7 trigger into the 'positionshown by Fig. 5 to release the pawl A which is then moved by its spring a into engagement with the ratchet teeth A, A as shown by Fig. 5. In the event of a further pull being exerted upon the plummet line the trigger will be displaced into the position shown in Fig. 6

in which an inclined flat surface 6 on the nose B bears against a corresponding surface a on the pawl A so that instead of tending to disengage the latter it will operate to moreifirmly retain .the said :pawl in l engagement with the ratchet teeth A, A as aforesaid.

What I claim and desire to secure by Let- ,ters Patent of the United :States'is 1. In a ubmarine mine comprising a flotation chamber constituting the mine proper, an anchor cable drum and a plummet for determining'ithe depth at which the flotation chamber is to be anchored beneath the sur- 'fLCGzOf the waterythe combination of'a member for engaging with the said drum, and a retaining device which is connected to the plummet and'holds said member out of engagement with the drum until the plummet touches the sea bed: I

2. In a submarinemine comprising a flotation chamber constituting the mine proper, a toothed anchor-cable drum and a plummet for determining the depth at which the flotationchamber'is to" be anchored beneath the surface of the water, :thecombination of a spring controlled pawl for engaging with the teeth :of said drum, and. a spring controlled trigger which 'is adapted to engage with the pawl and is connected "to the plummet. I I o In a submarine minecomprising a flotation chamber constituting the mine proper, an anchor cable drum and a plummet for de termining the depth at which the flotation chamber is to be anchored beneath the surface of the water,'the combination of a member for engaging with thcsaid drum, a re- Copies .of this patent may be obtained for five cents each, by addressing the Washington; .10.

for determining the depth at which the flotation chamber is to be anchored beneath the surface of the water, the combination of a spring controlled pawl for engagingwith the teeth of said drum, a spring controlled trigger which is adapted to engage with the pawl and is connected to the plummet, and means whereby, if a pull should again be exerted upon the trigger after the pawl has cmoved into engagement with the teeth, the

for determining the depth at which the flotation chamber is to be anchored beneath the surface of the water, the combination of a spring controlled pawl for engaging with the teeth of said drum, a lateral projection on said pawl, a spring-controlled trigger which is-connected to the plummet and has a nose for engaging with part of said projection to hold the pawl out of engagement with the teeth on the drum, said trigger nose having an inclined surface which, if a pull should again be exerted upon the trigger after :the pawl "has movedinto engagement with the teeth, will cooperate with a corresponding surface onxthe projection to hold the pawl all the more firmly in'engagement with the teeth. I v

6. In a submarin mine comprising a flotation chamberconstituting the mine proper, a toothed anchor cable drum and a plummet for determining the depth at which the flotation chamber is to be anchored beneath the surface of the water, the combination of a spring zcontrolled pawl for engaging with the teeth of saiddrum, a 'latena'l pin on said pawl, a :movable member normally lying in the path of said pm, but moved out of the path when the drum has made a'prede'termined number of revolutions, a spring controlled trigger which is connected to the plummet and has a nose for engaging with part of said pin to hold 'the'pawl out of engagement with the teeth on the drum, said trigger nose having an inclined surface which, ifa pull should again be exerted upon the trigger after the pawl has moved into engagement with the teeth, will cooperate with a corresponding surface on the pin to hold the pawl all the more firmly 1n engagement with the teeth. g 1 In testimony whereof, I aflix my signature.

THOMAS KEPPEL nonTH.

Commissioner of Patents,- 

